Piano sound augmentor



July l, 1969 J. w. .Q JTMEYER PIANO SOUND AUGMENTOR Filed April '7, 1967W /wum United States Patent 3,452,634 PIANO SOUND AUGMENTOR John W.Quitmeyer, 400 Oak St., Rochester, Mich. 49277 Filed Apr. 7, 1967, Ser.No. 629,243 Int. Cl. Gc 3/06 US. Cl. 84-194 3 Claims ABSTRACT OF THEDISCLOSURE My invention is a sound augmentor for a piano wherein a soundpost is ajustably mounted on the primary soundboard of the piano, and isdetachably connected by a clamp to the access panel of the piano, sothat the access panel provides an auxiliary soundboard to augment orincrease the sound output of the piano.

My invention relates to pianos and more particularly to the meansassociated therewith for producing musical tones therefrom.

In such pianos as the consoles and spinets, the soundboard area thereofis necessarily reduced because the sounding board must be made smallerto fit into the miniature case. Also, the effective soundboard area isfurther reduced by the heavy hard maple bridges, particularly the treblebridge, which runs diagonally from the lower left to the upper rightcorner of the soundboard. Thusly, the foregoing limitations in structureof such pianos results in a smaller efiective soundboard area and inmuch of the natural vibration of the soundboard being muted causing suchsmaller pianos to have a shallow tone quality in comparison with thelarger pianos.

In the past devices have been proposed to increase the soundboard areaof a piano, however, such devices have been directed to fastening theprimary soundboard adjacent to the supplemental soundboard, or toarrangements wherein the piano cannot be serviced or strings replacedwithout considerable difiiculty, and for these reasons, to the best ofmy knowledge and belief, such devices have not been used or beensuccessful in accomplishing the purpose for which such were intended.

It is therefore, a principal object of my invention to provide means toeffectively increase the freely vibratable soundboard area of a pianoWithout changing the overall dimensions or appearance of the instrumentand without interfering with the accessibility of the mechanism thereoffor service or adjustment.

It is a further object of this invention to substitute a secondary orauxiliary, easily detachable, soundboard in the place of theconventional forward lower access panel of a conventional piano.

It is another and further object of my invention to provide a soundaugmenting means for a miniature piano including forward auxiliarysoundboard means which may be easily removed to service the piano and ablind catch means for connecting said auxiliary soundboard to theexisting soundboard for the piano, said blind catch means simultaneouslyfunctioning as a sound post to transmit vibrations between suchauxiliary soundboard and the existing soundboard.

Another object of this my invention is to provide a magnetic latch meansfor connecting a forward auxiliary soundboard internally to the rearwardprimary soundboard of a piano.

It is to be understood that my invention possess other and furtheradvantageous features, some of which, with the foregoing, will be setforth at length in the following ,description where that form of theinvention which has been selected for illustration in the drawingaccompanying and forming part of the present specification is out3,452,634 Patented July 1, 1969 may be embodied in a plurality of forms.

Referring, now, to the drawing hereof:

FIGURE 1 is a sectional side elevational view of a spinet piano showingthe conventional features thereof and the application of my inventionthereto.

FIGURE 2 is a front cut-away view of the forward portion of the soundaugmenting means taken along line 2-2 of FIGURE 1.

FIGURE 3 is an elevational view of the auxiliary soundboard taken alongline 3-3 of FIGURE 1. 7

FIGURE 4 is an enlarged view of the blind catch means for securing saidauxiliary soundboard means to the sound post means and the primarysoundboard taken along line 4-4 of FIGURE 1.

FIGURE 5 is a cross sectional view of the structure of the sound posttaken along line 5-5 of FIGURE 1.

As indicated by the foregoing, my invention, designated in general bythe numeral 10, is shown incorporated in an upright piano of the spinettype. The casing 11 of said piano encompasses the mechanism of thepiano, the conventional parts of which comprise in part, a primarysoundboard 12, a metal plate 13 for supporting the strings 14 when theyare tuned. Said metal strings 14 are connected to a peg or pegs 15located at the bottom of said plate, strung over a bridge or bridges 16,and fastened to a tuning pin or pins 17 at the top of said plate. Thepiano 10 is further provided with a key bed 18, and a drop action 19with reversed abstract 19a commonly provided in such spinet pianoscausing the reduced soundboard area.

Forwardly of said drop action mechanism 19 and below said key bed anaccess opening 20 is provided in such conventional pianos for requiredaccess to the mechanism of the piano for servicing same. Said accessopening is generally rectangular in outline and is provided with walls21 formed by said casing 11 to receive a cover panel (not shown) toclose off said opening 20 when same is not being used. The bottom edge21: of said opening is provided with pins 23 for securing the coverpanel at its bottom edge, and a spring clip 22 is provided at the topedge 24 of said access opening to snap fasten the cover panel into saidaccess opening.

In accordance with my invention, I glued a wood block 25 to the back ofthe primary soundboard 12 at a predetermined spot 26 where the soundpost means 27 is to be attached, generally centrally located withrespect to said access opening. Directly in front of said spot, Idrilled a /2 inch hole or bore 28 through said plate '13. I theninserted a inch metal rod 29 having threaded ends 30 between adjacentstrings 14, through said bore 28 in said plate and threaded one end ofsaid rod through said soundboard 12 into said block thereby firmlyanchoring same to said primary soundboard. Next, I threaded a woodendowel 31 of suitable diameter 32 and predetermined length 33 onto theother end of said threaded rod 29. A pot magnet catch 34 is now attachedto the free, unsupported end 35 of said dowel by means of a wood screw36 entering an opening 37 in the center of said magnet. I now provide,further, an auxiliary soundboard 38 comprising a' thin wooden board orpanel 39 of generally rectangular outline mounted rigidly on a likewiserectangular frame 40 which extends around and adjacent to the edges 41of said panel 39. Said panel 39 is of thin cross-section so that somewill vibrate in response to vibrations transmitted to it through saidsound post means 27 as will become apparent from later disclosuresherein. A reinforcing rib 42 extends longitudinally and horizontallyacross said auxiliary soundboard substantially midway between the bottomedge 43 and the top edge 44 thereof, and a flat metal latch plate 45 issecured centrally to the face 46 of said rib by means of screws 47. Saidpot magnet catch is adjusted forwardly by rotating said dowel until saidmagnet joins forcibly with said latch plate when said auxiliarysoundboard is mounted in said access opening 20.

It is now apparent and understood that the auxiliary soundboard 38 maybe installed and removed in exactly the same manner as the originalpanel, because a slight pull exerted forwardly upon the upper portion 48of said auxiliary soundboard releases said magnet catch from said metallatch plate and said spring clip 22 disconnecting said sound post meansand allowing said auxiliary 1 soundboard to be removed from said accessopening for service on the inner mechanism of the piano. It is alsoapparent and understood that with said auxiliary soundboard in place andsaid sound post means integrally connected thereto and to said primarysoundboard, sound vibrations induced to said primary soundboard from thekeys 49 through said drop action to said strings are transmitted throughthe metal rod 29, the dowel 31, the magnet catch 34, the metal plate orlatch 45, the reinforcing rib 42, to the wooden board or panel 39,causing said panel 25 39 to vibrate in unison with said primarysoundboard and increasing the exposed freely vibratable soundboard areaof the piano 10 and thereby greatly improving the tone thereof.

Having now fully shown and described my invention,

said soundboard; walls defining a generally rectangular vertical accessopening positioned below said key bed and spaced a substantial distanceforwardly of said strings;

an improved sound augmenting device for increasing the freely vibratingsoundboard area of said piano comprising;

an auxiliary soundboard'panel of generally thin, flat,

rectangular outline, detachably mounted in and generally matching saidaccess opening;

a rearwardly positioned elongated cantilevered sound post element havingan adjustment portion fixedly fastened to said primary soundboard forextending said sound post forwardly between said strings with free endthereof terminating adjacent the rearward side of said soundboard panel;

and a blind catch member detachably connecting said rearward side ofsaid auxiliary soundboard panel and said free end of said sound post infixed relationship to each other when said panel is mounted in saidaccess opening so that said blind catch member and said sound postelement function together simultaneously as a unitary sound post totransmit vibrations between said auxiliary soundboard and said primarysoundboard, said blind catch member operable to readily release saidsound post when said auxiliary panel is moved forwardly and outwardlyfrom said access opening.

2. In combination with a piano having a casing, a primary soundboardvertically mounted in said casing, a plate mounted in said casingadjacent said primary soundboard having walls defining openings therein,a set of strings mounted upon said plate tuned respectively to thesounds of a musical scale; at least two bridges extending between saidplate walls, the bottom of said bridge mounted on saidprimary'soundboard and the top of said bridge supporting strings totransmit vibrations from said strings to said primary soundboard; a keybed mounted on said casing forwardly and projecting normal to saidsoundboard, walls defining a generally rectangular vertical accessopening positioned below said key bed and spaced a substantial distanceforwardly of said strings; and improved sound augmenting device forincreasing the freely vibrating soundboard area of said pianocomprising, an auxiliary soundboard panel constructed of generally thin,fiat, rectangular rigid material detachably mounted in said accessopening to substantially close said opening, an elongated rearward soundpost element fixedly mounted to said primary soundboard cantileveredforwardly between said strings having its free end thereof terminatingadjacent the rearward side of said soundboard panel and a clampingdevice including a latch element and a catch element connecting saidrearward side of said soundboard panel and said free end of said soundpost rigidly together when said soundboard panel is place into saidaccess opening.

3. In combination with a piano having a casing, a primary soundboardvertically mounted in said casing, a metal plate mounted in said casingadjacent said primary soundboard having walls defining openings therein,a set of wire strings mounted upon said plate for tuning respectively tothe sounds of a musical scale, at least two bridges extending betweensaid plate walls, the bottom of each bridge is mounted on said primarysoundboard and the top of each bridge supports said strings to transmitvibrations from said strings to said primary soundboard; an improvedsound augumenting device for increasing the freely vibrating soundboardarea of said piano, comprising, an auxiliary soundboard panelconstructed of generally thin, flat, rectangular, rigid material andmounted parallel to said primary soundboard adjacent said strings, andmagnetically responsive sound post catch means operable to interconnectsaid primary soundboard with said auxiliary soundboard to cause saidprimary soundboard and said auxiliary soundboard to vibrate in unisonwhen said strings are activated.

References Cited UNITED STATES PATENTS 711,765 10/ 1902 Heppe 84-1942,995,983 8/ 1961 Davis 248206 3,031,799 5/ 1962 Bradsby 248206 RICHARDB. WILKINSON, Primary Examiner.

L. W. FRANKLIN, Assistant Examiner.

U.S. Cl. X.R. 248206 a

